Software Engineer, LLM Infrastructure

About Us:At Fireworks, we’re building the future of generative AI infrastructure. Our platform delivers the highest-quality models with the fastest and most scalable inference in the industry. We’ve been independently benchmarked as the leader in LLM inference speed and are driving cutting-edge innovation through projects like our own function calling and multimodal models. Fireworks is a Series C company valued at $4 billion and backed by top investors including Benchmark, Sequoia, Lightspeed, Index, and Evantic. We’re an ambitious, collaborative team of builders, founded by veterans of Meta PyTorch and Google Vertex AI.In the last few months alone we launched Fireworks Training, partnered with Microsoft Azure Foundry, and published research straight from our production systems. A few examples of what that looks like in practice:Frontier RL is cheaper than the mega-cluster narrative suggests: we ran cross-region rollouts using 98% sparse weight deltas and published what we learned. (blog)Open source agents with frontier advisors: matching frontier performance through training and harness engineering. (blog)The fine-tuning bottleneck is not the algorithm: integration friction and iteration speed are what actually stall teams; we documented the patterns across dozens of customer engagements. (blog)The Role:As a Software Engineer on our AI Infrastructure team, you will help design the core systems that power Fireworks AI’s generative AI platform. You will help build infrastructure and tools that ensure the reliability, performance, quality, and availability of our AI system. Our mission is to make Fireworks AI the most reliable and user friendly generative AI platform in the world. You will partner closely with our cloud infrastructure team, product team, and performance team to deliver infrastructure that bridges the gap between our customer and the ultra-performant proprietary Fireworks inference engine. Key Responsibilities:Contribute to the design and development of scalable backend infrastructure that supports distributed training, inference, and data pipelinesBuild and maintain core backend services such as LLM CI/CD pipeline, control plane, and model serving systemsSupport performance optimization, cost efficiency, and reliability improvements across compute, storage, and networking layersBuilding frameworks and safeguards to ensure Fireworks AI has the best model quality in the industryCollaborate with performance, training, and product teams to translate research and product needs into infrastructure solutionsParticipate in code reviews, technical discussions, and continuous integration and deployment processesMinimum Qualifications:Bachelor’s degree in Computer Science, Engineering, or a related technical field (or equivalent practical experience)3 years of experience in software engineering, with a focus on infrastructure or machine learning systemsStrong programming skills in Python, Go, or a similar languageProven experience in ML infrastructure and tooling (e.g., PyTorch, MLflow, Vertex AI, SageMaker, Kubernetes, etc.).Basic understanding of LLM knowledge (e.g., context length, disaggregated prefill, KV cache memory estimation, etc) Preferred Qualifications:5+ years of experience in software engineering, with a focus on infrastructure or machine learning systems Experience with open source inference engine like vLLM, Sglang, or TRT-LLM Contributions to open-source infrastructure or ML projects Experience in building large scale ML/MLOps infrastructureWhy Fireworks AI?Solve Hard Problems: Tackle challenges at the forefront of AI infrastructure, from low-latency inference to scalable model serving.Build What’s Next: Work with bleeding-edge technology that impacts how businesses and developers harness AI globally.Ownership & Impact: Join a fast-growing, passionate team where your work directly shapes the future of AI—no bureaucracy, just results.Learn from the Best: Collaborate with world-class engineers and AI researchers who thrive on curiosity and innovation.Fireworks AI is an equal-opportunity employer. We celebrate diversity and are committed to creating an inclusive environment for all innovators.